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Journal of Rare Earths 2024年第3期42卷 600-611,I0006页

作者： guojian Lin Lu Li Zhengwei Guo Xianjun Jia Xiao wang Zhentao Yuan Guoxing Zhang Yun Zhan Quan Shan Zulai Li Faculty of materials science and engineering Kunming University of Science and TechnologyKunming650093China Research Center for Analysis and Measurement Kunming University of Science and TechnologyKunming650093China City College Kunming University of Science and TechnologyKunming650051China

To develop pure aluminum alloys with high conductivity and strength, Al-0.2Ce and Al-0.2Ce-0.1Y alloys were prepared by rolling and annealing processes in this study. The effects of trace rare earth elements on the strength and electrical conductivity of the pure aluminum alloys were investigated. It is revealed that the addition of Ce and Y to pure aluminum can effectively enhance the strength and electrical conductivity of the alloys. In Al-0.2Ce, the addition of Ce can effectively refine the grain size of a-Al, with an average grain size of 90.68 μm in the as-cast state. The grain size of the alloy is further reduced to 87.55 μm by the simultaneous addition of Y. The synergistic addition of Ce and Y changes the properties of the alloy. The addition of Ce and Y also produces the Al_(11)Ce_(3) and Al_(3)Y second phases, which have coherent relationship with a-Al. The two-dimensional mismatch degree was calculated to be only 4.43%and 0.85%, respectively, which can provide a certain amount of nucleation substrate for a-Al in the incubation stage. The interfacial match between the L1_(2)structure of Al_(3)Y and a-Al was calculated using first-principles simulations. The results indicate that Al_(3)Y has a strong bonding effect with a-Al. Nanoscale second phases at grain boundaries can be effective in reducing resistivity due to dislocation *** second phases with better matching interfaces to the substrate have no positive effect on the scattering motion of electrons.

关键词： Pure aluminum Rare earths Impurity purification First-principles calculations Strength-conductivity contradiction

SIDEBANDS OF X-RAY DIFFRACTION IN AGE-HARDENED Cu-Ti ALLOY

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中国有色金属学会会刊：英文版 1996年第4期6卷 87-93页

作者： Wei Yinghui wang Xiaotian(school of materials science and engineering,Xi’an Jiaotong University,Xi’an 710049) school of materials science and engineering Xi'an Jiaotong University Xi'an 710049 China

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关键词： Cu-Ti alloy X-ray diffraction sidebands static lattice wave theory

Dislocation Densites of Deformed Steel Sheets Based on Positron Annihilation

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International Journal of Minerals,Metallurgy and materials 1998年第1期12卷 47-50页

作者： Yonglin Kang Xianjin wang (materials science and engineering school, University of science and Technology Beijing, Beijing 100083, China) materials science and engineering school University of Science and Technology Beijing Beijing 100083 China

The variation regularity of dislocation densites of some deformed steel sheets under three kinds of strainpaths as uniaxial tension, plane strain and equal biaxial stretching was investigated by means of positron lifetimespectrum and Doppler-broadening techniques. The results show that the increasing rate of dislocation densites isrelated to the plastic strain path. A relationship between the increasing rate of micro-defects, macro-instability andforming limits during the process of steel sheet forming was got based on analyzing the mechanism of dislocationdensity increasing under different stress-strain condihons.

关键词： positron annihilation dislocation steel sheet strain path

Sol-gel Preparation and Infrared Radiation Property of Boron-substituted Cordierite Glass-ceramics

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Journal of materials science & Technology 2010年第5期26卷 445-448页

作者： Shuming wang and Fenghua Kuang school of materials science and engineering,University of science & Technology Beijing,Beijing 100083,China school of materials science and engineering University of Science & Technology Beijing Beijing 100083 China

Boron for aluminum substitution in the cordierite structure has been examined by sol-gel preparation of different samples along the compositional junction Mg2Al4-xBxSi5O18 with x=0,0.5,1,*** increasing the x value from 0 to 1.5 the crystallization behavior changed *** amount B2O3 doping can promote the sintering of amorphous cordierite gel,effectively restrain the precipitation of μ-cordierite and enhance the crystallization of α-*** substitution of B3＋ for Al3＋ in cordierite crystal structure can effectively improve the near-infrared spectral emissivity of this cordierite based glass-ceramics.

关键词： Sol-gel Glass-ceramics Infrared radiation B3+ substitution Solid solution

Emergent ultra-high temperature ferromagnetism in La_(2)CoO_(4±x) thin films

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Nano Research 2024年第8期17卷 7250-7255页

作者： Ziang Meng Han Yan Peixin Qin Zhuo Yin Peiheng Jiang Xiaorong Zhou Xiaoning wang Hongyu Chen Li Liu Zhiyuan Duan guojian Zhao Weisheng Zhao Fengxia Hu Qinghua Zhang Zhicheng Zhong Zhiqi Liu school of materials science and engineering Beihang UniversityBeijing 100191China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China CAS Key Laboratory of Magnetic materials and Devices and Zhejiang Province Key Laboratory of Magnetic materials and Application Technology Ningbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201China Fert Beijing Institute School of Integrated Circuit Science and EngineeringBeihang UniversityBeijing 100191China

Searching for novel ferromagnetic oxides with high Curie temperature(TC)has been one of the main goals for oxide *** well-known perovskite cobaltate LaCoO_(3) is a classical ferromagnet in its thin-film form;however,it suffers from a low TC(~85 K).Here we report a new type of ferromagnetic La-Co-O films with an ultrahigh TC of~820 *** are fabricated by pulsed laser deposition from a LaCoO_(3) target at low oxygen partial *** structural analysis indicates that they crystallize in terms of the Ruddlesden–Popper phase of La_(2)CoO_(4±x).In sharp contrast to the antiferromagnetism of bulk La_(2)CoO_(4),the strong ferromagnetism in the La_(2)CoO_(4±x) thin films is firmly demonstrated by magnetometry measurements,X-ray magnetic circular dichroism characterization,and magnetotransport *** importantly,density functional theory calculations indicate that the nonstoichiometric oxygen induces an antiferromagnetic-to-ferromagnetic phase transition,accompanied by the orbital reconstruction of Co 3d ***,our study provides an attractive strategy for designing or synthesizing exotic magnetic oxides with high ordering temperatures.

关键词： ferromagnetic oxides ultra-high Curie temperature La_(2)CoO_(4) spin current transport oxygen engineering

Application of the Long-Chain Linear Polyester in Plastification of PVC

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Journal of Wuhan University of Technology(materials science) 2008年第1期23卷 100-104页

作者：李岩 school of materials science and engineering Tongji University

The plastification modification of poly （vinyl chloride）（PVC） with the long-chain linear polyester （LP） synthesized by linear dodecanedioic acid （DC12） or tetradecanedioic acid （DC14） with different diols is investigated. The processing characteristics, mechanical properties and extraction property of the PVC/LP blends in different solvents （xylene, cyclohexane, ethanol） were also studied in detail. All results were compared with that of the PVC plasticized with dioctyl phthalate （DOP）. The results show that the molecular weight, molecular structure and loading of LP greatly influence the mechanical properties of the PVC/LP blends. The processability and the mechanical properties of PVC plasticized by LP are comparable to those of the corresponding PVC/DOP blends. However, the PVC/LP blends posses much better migration resistance property than the corresponding PVC/DOP blends, which makes the long-chain linear polyester become a very good plasticizer candidate for PVC industry.

关键词： poly (vinyl chloride) long-chain linear polyester DOP plasticizer migration resistance

Influence of Mo on the microstructure and mechanical properties of TiC-based cermets

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Rare Metals 2010年第4期29卷 346-350页

作者： wang Xingqing,HE Xiaoxiang,and GUO Hailiang school of materials science and engineering,Shanghai University,Shanghai 200072,China school of materials science and engineering Shanghai University Shanghai China

The microstructures and mechanics properties of TiC-based cermets composed of TiC, WC, Ni, Co, Mo, and Cr3C2 were investigated. The results show that Mo has a great effect on the sintering densification, microstructures, and mechanical properties. The microstructures and distribution of Mo and Ti in the TiC-based cermets were analyzed. It was indicated that a new phase with Ti, Mo, W, and C was formed on the rim of （Ti,W）C grains by means of an addition of Mo into the TiC-based cermets. The new phase with a surrounding structure was of great aid to improve the wettability of the liquid phase on the solid phase surface of TiC, decrease the porosity and refine the grains of the hard phase, which gave rise to the increase in strength and hardness. The properties of the TiC-based cermets could be further improved to some extent by adding WC, Cr2C3, and Co.

关键词： TiC-based cermets Mo effect sintering densification microstructure mechanical properties

Fabrication of pure copper rods containing continuous columnar crystals by continuous unidirectional solidification technology

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Journal of University of science and Technology Beijing 2004年第3期11卷 240-244页

作者： Hong zhang Jianxin Xie Zidong wang materials science and engineering school, University of science and Technology Beijing, Beijing 100083, China Mat. Sci. and Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Pure copper rods containing continuous columnar crystals were fabricatedusing the downward CUS (Continuous Unidirectional Solidification) equipment. When the technologicalparameters were set as the ranges of mould temperature 1100-1300℃, cooling distance (the distancefrom the exit of the cast mould to the start point of cooling) 10-20 mm, casting speed 0.2-2.5 mm/s,cooling water (20-25℃) volume 1000-1320 L/h, and when these parameters matched reasonably, the CUSprocess was performed stably, and pure copper rods containing continuous columnar crystals withbright and smooth surface were produced. The dendritic arm spacing of the crystals in copper rodsdecreased with increasing the casting speed. The results of the texture by X-ray diffractionanalysis showed that the rods has strong fiber texture.

关键词： copper continuous unidirectional solidification mould temperature castingspeed microstructure texture

EFFECT　OF　MILLING　INTENSITY　ON　STRUCTURAL　CHANGES　OF　MIXED　Al－Fe－Ni　POWDERS　IN　MECHANICAL　ALLOYING　PROCESS

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中国有色金属学会会刊：英文版 1996年第3期6卷 143-145,149页

作者： Liu Zuyan Liang Guoxian wang Erde(school of materials science and engineering,Harbin Institute of Technology, Harbin 150001) school of materials science and engineering Harbin Institute of Technology Harbin 150001 China

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关键词： Al-Fe-Ni powder structural change milling intensity mechanical alloying